This Mentored Clinical Scientist Research Development Award (K08) will enable the applicant to develop expertise designing and implementing studies using performance-based tasks as a methodological tool for investigating etiological processes that are not easily accessible via introspection. Alcohol is the most commonly used drug in adolescence, with higher levels of drinking being robustly associated with cannabis use (the second most used drug) and externalizing and internalizing problems. Dual-process models explain heterogeneity and co-morbidity of alcohol use by postulating individual differences in motivation and cognitive control as risk factors for problematic drinking Different theoretical perspectives have emerged; some construe motivation as individual differences in reinforcement sensitivity, others as drug-specific memory associations. Motivational and cognitive control risk factors have been shown to predict externalizing and internalizing psychopathology, and hence dual-process models can elucidate who is at risk for drinking, and why drinking frequently co-occurs with other drug use and externalizing/internalizing problems. This project will be the first to concurrently test alternatie conceptualizations of motivation in dual-process models, and to examine the multi- dimensional structure of cognitive control in dual-process models. A better understanding of specific mechanisms in the development of drinking can inform our theoretical understanding of addictions, and potentially lead to interventions that target idiosyncratic etiological mechanisms. Training involves original data collection; 150 18-20 year olds are proposed to be sampled from a larger NIAAA funded project examining the development of drinking milestones. A battery of performance-based tasks will be administered to the sub- sample upon completion of participation in the larger study; tasks will measure different facets of motivation (reinforcement sensitivity, drug specific memory associations) and cognitive control (set-shifting, inhibition, working memory capacity). Web-based survey methods will be used to provide a short-term prospective test of dual-process models as applied to: alcohol and cannabis use/problem use, and symptoms of externalizing and internalizing psychopathology. The association of alcohol involvement with cannabis use, and externalizing and internalizing symptoms is expected to be attenuated after accounting for shared etiological mechanisms. This research will lead to subsequent R01 grant applications involving: 1) different pathways to the initiation of drinking, 2 the emergence of alcohol and cannabis use disorders in late-adolescence/young adulthood, and 3) transdiagnostic etiological models of alcoholism and psychopathology. This K08 will train the applicant for an independent research career in the field of addictions by expanding the breadth and depth of my programmatic line of research.